Geology

The Magaliesberg Range has a very long geological history. Its quartzites, shales, chert and dolomite were deposited as sediments in an inland basin on top of the 3 billion year old Archaean Basement Complex. This process of sedimentation lasted for about 300 million years. About 2 billion years ago a massive upwelling of molten magma resulted in what is now known as the Bushveld Igneous Complex. The enormous weight of this intrusion depressed the sediments that lay beneath and tilted the sediments along the edges so that the broken scarps faced outward and upward, and the gentler dip slopes inward. During the same period these sediments were fractured and igneous intrusions filled the cracks. With the passage of time these intrusions eroded, especially on the dip slopes, forming deep kloofs or ravines providing excellent rock-climbing potential to modern man. This large dogbone-shaped area is now termed the Transvaal Basin and includes the lofty escarpment of the Transvaal Drakensberg overlooking the Lowveld in the eastern part of the country. Massive outpourings of igneous material of the much younger Karroo System later covered the Transvaal Basin, but was subsequently eroded so that it only remains along the Transvaal Basin's southern rim.

Climate

The range forms a natural barrier between the lower lying Bushveld to the north and the cooler Highveld to the south. The range receives rainfall in summer in the form of thunderstorms, with an average of 650mmm annually. In winter frost occurs frequently in the valleys on the southern side of the mountain, but almost never on the northern slopes.

The later inhabitants of the mountain range called them the Kashan mountains, but the name was later changed to Magaliesberg after the Tswana chief Magali who ruled his tribe at the same time the Voortrekkers were entering this area. In the nineteenth century, explorers such as David Livingstone and William Cornwallis Harris traversed the area and made contact with some of the tribes living there.

In 1822 Shaka sent his most trusted commander, Mzilikazi, to conquer the Sotho tribes of the region. After accomplishing this task, Mzilikazi decided to break away from Shaka and found his own nation, the Matabele. As he feared an attack from Shaka if he returned home he settled in the Magaliesberg regions.

On 17 January1837, after some Voortrekkers had been attacked and killed by Mzilikazi's impis they counter-attacked and, under the leadership of Hendrik Potgieter and Gerrit Maritz, drove the Matabeles north across the Limpopo River. The Boers subsequently settled in the valleys of the Magaliesberg Range and turned the region into some of the most productive farmland in South Africa.

The area saw some heavy fighting during the Second Anglo-Boer War. The Boers, being extremely familiar with the mountains, used secret pathways across the mountains to launch guerrilla attacks on the Britishsoldiers. In response, the British forces built blockhouses on top of the mountains in order to restrict the movement of the Boer forces; ruins of these structures are still to be seen on the mountain.

Control of the Magaliesberg Mountain Range was of great importance to both the Boer and the British forces, especially the two routes between Pretoria and Rustenburg, which crossed it at Silkaatsnek and Kommandonek, respectively. As a result many battles, such as the battles of Buffelspoort, Nooitgedacht and Olifantsnek were fought in the area.

After the war, farms in the area were reoccupied and farming was resumed, tobacco and citrus being particularly successful.

In 1923 the Hartbeespoort Dam, situated in one of the valleys of the range, was completed. It became a popular holiday and weekend destination for the inhabitants of Johannesburg and Pretoria, and the village of Hartbeespoort was created as a result.

At present the Magaliesberg area is still largely agricultural, although tourism is a rapidly growing industry in the area.

Kgaswane Mountain Reserve is a nature reserve above Rustenburg covering 4257ha of the Magaliesberg.
Numerous smaller reserves, private and state, are to be found along the length of the range.